Fuze



Sept. 23, 1947. R. L. GRAUMANN Er AL FUZE Filed July l, 1942 4 Sheets-Sheet 1 6 0 2 5 \\\\\\\H 3 /Y v VAWI 7 my `M Mm f 5&26 39 29 031.

Raymond BY Willi/Q Il@ lll ' 5 sa as 29 304.5

Patented Sept. 23, 1947 Raymond L. Gfraumann, Alexandria,. Va., and-4 William J. Donahue, Jr., Washington, D. C.

Application' July 1, 1942; Serial No. 449,324

(Granted under the act of March` 3; 1883i as amended Aprilf30, 1928; 370 0. G. 757) Claims.

This inventiony relates to improvementsin explosive projectiles of the bore safe type, a particular purpose being to assure the lack of continuity of the explosive train until the projectile actually begins its flight from the muzzle of the gun. Thereupon the `centrifugalforce developed by the spinning of the projectile becomes -eiectve to establish the continuity of the explosive train. in readiness for the flringtherof when the projectile strikes the target.

The general principle just stated isgiven mechanical expression herein in a number of ways, the disclosure comprising, two types` of fuzes, namely super-sensitive fuzesfwhich'will function instantaneously upon impact with a relatively fragile substance, such as the fabric of an airplane, and insensitive fuzeswhich will function instantaneously upon impact with more solid substances, such as the Istructural members andarmored parts of an aircraft ortheir equivalents.

With this preamble in mind it can readily be understoodthat oneof the objects of the invention is to provide a nose fuze which is contrived to insure the deferment of registrationY ofY the components of the explosive train with the firing pin or its equivalent, until the projectile is subjected tooentrifugal and/or set-back forces such as willordinarily be developed therein only upon firing said projectile from a gun.

Another object of the invention is to provide a nose fuze which in most of its forms employs a firingpin for the detonation of the explosive train, said ringpin being locked in a predetermined position in respect to the explosive train in which position saidY pin directly holdsthe movable' component yof said train in-an unarmed or safeposition, or itself is held ina retracted-position wherein itis incapable of detonating said train4 upon accidental dropping of theprojectile upon its. nose if the explosive train were by, some remotechancefto assume an armed positionA in respect to the firing pin.

A further object of'the invention isto provide a nosefuze wherein the firing. pin can be releasedfroni its locked'position in respect` to the explosivetrainY only in response: to one of the forces set* up in the projectile astheV result ofzits being fired-from a gun.

(Btl-1er: objects and advantageswill appear: in

the followingspecication, referencel being made tothe accompanying drawings in which:

Fig. 1'. is a longitudinalse'ction of a nose fuze wherein. the firing pin' isusedto lock the rotor in the unarmed positionzinirespect to the explosive train and itself is locked'in an unarmed position in respectto the rotor;

Fig. 2 is a cross section taken on the line 2i-2 of Fig. 1.

Fig. 3 is a longitudinal 'section of Fig. 1, showing the firing pin and rotor in their respective `armed positions:

Fig. 4 is a fractionallongitudinal section of a nose fuze illustrating a modied lock` for the firing-pin.

Fig. 5 is a cross-section taken on the line 55 of Fig. 4'..

Fig, 6`is a" fractionallongitudinal section of another modie'd'form of nose fuze employing-a shorter firing pin;

Fig. 7 is a longitudinal section of a nose fuze wherein the firing pinis` used to lock a, slider in the unarmed' position in respect to the explosive trainandlitself is locked'in'an unarmedposition byr a split ring.

Fig. 8isa crosssectiontaken on the line '8e-8 of Fig. 7."

Fig..9. is a fractionalllongitudinalsection of a slider type" nose fuze wherein the firing pin is held retractedby-centrifugal1y actuated detents and'a` split ring.

Fig; 10"isl a section taken on line lU--Illl of Fig. 9.'

Fig; 11 is a--crossl section taken'on line ll-ll of' Fig: 9.`

Fig. 12` is `a'fractional llongitudinal section of a noseiuzewherein centrifugally actuatedldetents are-used inconjunction-with a firing pin` and a rotor;

Fig. 11i-isI a planviewx of the rotor shown inA Fig. 1.2L

Fig. 14 is a fractional longitudinal sectionfof a `rotor-type nose fuze employing a modified :firing pin and split* ring" assemblage.

Fig.y 15` is a longitudinal `sectionof a nose fuze employing azyoke 'spring'. in conjunction with the 'ring pinv and rotor detents.

Fig. 16.4is a-view'- similar to Fig.: 15 showing the parts iin 't the ringz'position, after-impact.-

l5?ig,f.1.7l isiairactional .longitudinal section `of a 3 rotortype nose fuze employing a Crusher-type firing pin housing.

Fig. 18 is a fractional longitudinal section of a rotor-type nose fuze wherein the explosive train is detonated solely by the shock of impact.

Fig. 19 is a fractional longitudinal section of a modification of the nose fuze in Fig. 18.

Fig. 20 is a fractional longitudinal section of another modification of the nose fuze in Fig. 18, wherein the nose disc is supplemented by a firing pin.

Fig. 21 is a fractional longitudinal section of a rotor-type nose fuze wherein ring is accomplished by `a blind nose cap.

In carrying out the invention provision is made of a, fuze 25, so identified in all of the forms thereof, each of said forms comprising a body 26 which has a boss 2l threaded at 28 for screwing into the nose of an explosive projectile. rI'he body 28 includes a boss 29 provided with threads l3o to. which a nose cap 3l is screwed. There is a departure from this particular structure in one of the forms (Fig. 15) but in all instances the body 26 contains a chamber 32 which is occupied in Y part by a carrier 33.

This carrier is movable by centrifugal force from aninitially unarmed or safe position to an armed or ring position in all forms of the invention'. Detent means is used in each form of the invention to hold the carrier in' said unarmed position,v and the description is devoted to the variations involved in this particular phase of the invention as well as to variations in other details.

The forms of the invention shown in Figs. 1 to l16V are known as the super-sensitive type of fuzes because they are capable of firing the explosive charge of the projectile by contacting relatively fragile objects, such as the fabric of an aircraft to which a less sensitive fuze would not respond. In Figs. 1, 2, and 3 an internally threaded bore 34 provides the mounting for a booster thirnble 35. `A booster 36 is held inthe thimble by suitable means, there being communication between the booster and the chamber 32 through a lead 31 which, with a detonator 38, completes. what is'lher'ein known as an explosive train. The carrier 33contains the detonator `38, and because of its mobility controls the continuity or lack of continuity of the explosive train,

The lead opens directly into the chamber 32, almost touching the contiguous side of the detonator carrier 33. Initially the detonator 38 is held` out of registration with the lead 37 by the previously mentioned detent means which engages the carrier. For this purpose the carrier which is turnably pocketed inthe chamber V32, has a recess 39 which is occupied by the point of the ring pin 40 to prevent turning. The recess is radially spaced (Fig. 3) from the detonator 38 for which reason the detonator necessarily isV in the non-'registering position when the ring pin is engaged with the recess as stated. A pair of weights 4l (Fig. 3) are sustained in the carrier in an unbalanced Vrelationship to the fuze axis, awaiting the moment of release from the ring pin. Y Y Thejring pin is rlxedly attached at itsouter Yend to the head end 42 of a sleeve 43. A flange 44 on the other end of the'sleeve engages a partition 45 which also provides the abutment for the rear end of a spring 4B. The outer end of said springabuts the head 4,2, tending to displace the firing pin assembly; consisting of the firing pin 49 andthe sleeve'43, outwardly. Thistendency 48 and cap 3| by action of the spring 45.

4 is prevented by the engagement of a pair of frangible tabs 41 (Fig. 2) on the sleeve 43 with a setback collar 48. This collar occupies the front end of a chamber 49 in the nose cap 3|, being held there by the force delivered thereto through the contacting tabs 4l.

Upon ring the projectile equipped with the nose fuze 25 from a gun, the inertia of the setback collar` 48 causes the movement of said collar toward the rear end of the chamber 49. The tabs 4l are sheared from the sleeve 43, and the collar 48 comes to rest against the flange 44. At the cessation of the aforesaid inertia or set-back force, which also affects the firing pin assembly, and as the projectile leaves the muzzle of the gun,

said firing pin assembly moves outwardly in theV Y matching bores 50, 5l respectively in the collar The collar 48 is then moved outwardly because of the engagement of the flange 44 therewith (Fig. 3). rIhe withdrawal of the point Yof the firing pin from the recess 39 leaves the carrier 33 free to turn under the centrifugal force which acts upon the projectile. The weights 4l ily as far out as possible (Fig. 3) thus turning the carrier 33, thereby aligning the explosive train 36, 31, and 38 with the firing pin. Upon striking the target the ring pin assembly is driven inwardly, causing the firing pin to stab the detonator 38 and i'lre the booster `36. Thereupon the projectile ller is exploded. The feature of the form of the invention shown in Figs. 1, 2, and 3 is the employment of the firing pin 40 as the detent for locking the carrier 33 in the safe or unarmed position, the spring lift for the firing pin assembly, in turn, being held in the safe or unarmed position by the combination of the frangible tabs 4l and the setback collar 48. Y f Figs. 4 and 5 show the second form of the invention which is similar tothe form shown in Figs. 1, 2, and 3, the main distinction between the two forms being in the use of a split ring 52 to maintain the firing pin 40 in the unarmed position.V This ring is substituted for the frangible tabs 4l since it'normally restrains the spring 46 and thereby holds the firing pin assemblage 49, 42 in the retracted position (Fig. 4). Said ring 52 initially remains seated upon the sleeve 43 between the flange 44 and the front Wall of the chamber 49. This keeps the firing pin in locked'relationship to the carrier 33.

Upon ring this projectile, the centrifugal force opens the split ring 52, thereby releasing the firing pin assembly 48, 42. When the set-back force ceases, which `force initially holds the vfiring pin assembly back, said assembly moves forwardly by action of the spring'li. The travel of the assembly is limited bythe engagement of the flange 44 with the front wall of the chamber 49. The head 42 is then in an exposed position, in readiness to detonate the explosive train upon contact with the target. It will be understood that the carrier 33 is turned upon its release from the point of the ring pin as in the case of the previous example by the same centrifugal force which earlier spread the ring 52, the detonator 38 thereby completing the registration of `the explosive train with the firing pin.

Fig. 6 Will be recognized as a structure substantially the same as that of the fuze in Fig. 4. The split ringi52 is used as is alsoits centrifugal expansion in the chamber 49'for the release of the ring pin assembly 40, 43. The latter is made shorter than in Fig, 4, thus enabling the fuze to be sealed with a thin disc y53. Said-disc is seated by a` nose crimp 54.in the otherwise open end-of the. bore. 5I. Theturnable carrier. 33 is locked initially by the engagement of the point of the ringpin 40 in the recessn39. The release of the firing pin assembly allows the spring 46 to displacesaicl` assembly so that the carrier becomes free to moveV under the influence of centrifugal force.

A hole. 5.5` provides for. a back-flow of air from the space between thehead. 42 and. the.v disc 53 to avoid a. compression. of air which would check the motion off the tiring; pin assembly.. Upon thev striking of the projectilethenose crimp 54 cutsy a, wad from. the. target, thus shearing the disc 53 andidriving the firing pin` assembly backwards to.- detonate the then. aligned explosive train.

Figs. 7 and 8 differ chiefly from Figs. 1, 4, andA 6 by making thecarrier 33 in4 slider form. The body 56. is. cylindricalv to fit the bore 51 which is driveninfrom. one sideof the body 26. The rabbeting at 58 (Fig. 8)- of opposite sides of the body 56 overloalances.the slider. A pin 59 mounted on the body 26Y (Fig. 7) to project into one of the rabbet spaces (Fig. 8) keeps the detonator 38- in a registrable position with the rest of the explosive train and the firing pin assembly-by preventing the slider from turning in its bore.

The sleeve 43 of the firing pin assembly is guided both in the bore 5I and an extension 66 thereof in the boss 23of the fuze body 26. The flange da is located on the sleeve 43 at a place medially of the ends of the sleeve to suit this particular mode of slidable mounting. The split ring 52 holds the spring ein check as before, initially keeping the firing pin assembly in its locking position in reference to the detonator carrier. l

Upon ring the projectile carrying the nose fuze asshownin Fig'. 7, the split ring52, firing pin assembly 4D; i3 and carrier 33 make the same sequential responses as in Figs. 4- and 6. The overbalanced slider-carrier moves over against a cover 61, thus bringing the detonator 33m line with the ring pinand the rest of the explosive train. Saidcover is secured in place between the body 25 andthe nose cap 3| as shown when the two are screwed together.

Figs. 9, 10,' and 11 illustrate the use of detent plugs 6 2"4 and 63 both in conjunction with the slider. carrier 33 and the split ring 52. Said cletentsare desirably employed in pairs, thus providing an arrangementwhich is balanced throughout, except in the carrier itself. Here a lead' slug 6d is used to overbalance the carrier and make sure that the carrier will move out in-its bore 51 against the cover 6i by centrifugal force, when permitted to do so.

The detents 62 are slidably pocketed in thimbles 35 in common with springs 66. Each thimble is forced the required distance into a lateral boreV 6l extending from the bore 51 to properly position the pin end 4t8 in an openingin the side ofthe carrier. The carrier is thus held initially by spring-pressed plugs instead of being detained by the ring pin 4D; The firing pin has a collar 69'beside which the detents 63 are stationed to prevent premature inward displacement of the firing pin. This collar slidable fits a central -hole 10 in the boss 29 (Fig. 10) the lateral bores ll-of which are occupied by the detents 63.

A pad I2 constitutesl the outer terminal of the ring pin lill.r Said padis `positionedpclose tothe thin disc Eli-Which, in this case, is clamped at itsw peripheral ange between the nose cap 3| and a crimp tip 13. Upon firing a projectile equippedV with this fuze, the centrifugal force willcause the detent plugs 63 to move outwardly against the split ring 52` opening it and releasing the firing pin 46. The centrifugal force also causes the detent plugs 62 to move outwardly, compressing the springs 66 and releasing the slider-carrier 33 which is overbalanced by the lead-slug 64, said slider moves over against the cover 6l, thus bringing the detonator 38 in line with the firing pin and the rest of the explosive train. The same centrifugal force which displaces the detent plugs 62 and the carrier 33 in serial order, exercises a stabilizing effect upon the carrier, preventing any tendency toward its turning on its axis and therefore keeping the detonator 38 in alignment with the firing pin 4U. When striking the target the crimp tip 'I3 cuts a wad which is driven backwardly in the bore 5I, rupturing the disc 53 and displacing the firing pin to strike the detonator.

Fig. 12 will be recognized as similar to Fig. 10, the main diiference being the substitution of a turnable carrier similar in general to that of Fig. 1 for the slider-carrier of Fig. 10. A minor dii-ference comprises slidably mounting the detent plugs 62 directly in the lateral bores 6l instead of confining them to thimbles 65 as in Fig. 10. The springs 36 bear against the cover 6| at their outer ends. The pin ends 68 initially engage in recesses 39 in the flat sides of the turnable carrier 33, restraining the turning thereof under the influence of the centrifugal force upon its weights 4l (Fig. 13) until the detent plugs 63 are centrifugally displaced sufficiently far out. Otherwise the same actions occur as in the fuze shown in Fig. 10 upon ring the projectile.

Fig. 14 is to be regarded as the sam-e type of fuze as Fig. l2. The turnable carrier 33 is initially held by detent plugs as in Fig. 12. However, the detent plugs 63 are omitted, the split ring 52 being used alone in conjunction with the firing pin sleeve e3. Said sleeve has a flange ed' which is initially obstructed by the split ring 52Y to hold the firing pin 40 in its outward position. The internal action of this fuze during the flight of the projectile is the same as that of the fuze in Fig. 12, noting the omission of the detent plugs 63, as is also the internal response when the crimp tip 'I3 strikes the target.

Figs. 15 and 16 illustrate a type of fuze wherein the modification occurs mainly in the firing pin assembly. The chamber i9 in the boss 29 now consists of passageways merely wide enough to accommodate the diverging arms 'Hl of a yoke spring '15. A shoulder i6 is provided in the formation of the chamberpassageways 49, with which thetips .oi the arms 'M are abutted initially as shown in Fig. 15. The circumferential limits of the two shoulders comprise external reliefs past which the tips of the arms are moved by centrifugal force, thereby to escape the shoulders. The yoke spring 'l5 is secured centrally to the pad 12 of the ring pin B6, which pad, as in Figs. 9 and 10, is slidable in the bore 5i at the forward terminal of the fuze.

Plug detents 62 are used in conjunction with the turnable carrier 33, said detents being held in their initial spring arms M which, in turn, are held locked because of their abutment against the shoulder 16. Upon cessation of the set-back force set up in the fuze when firing the projectile, the centrifugal force causes the detent plugs 62 to move outwardly, spreading the yoke spring I outwardly away from the shoulder 16 and driving the tips of the arms 14 against the cover 6l. The ring pin 49 remains in the forward position during iiight due to the friction between the yoke spring arms 14 and the cover 6l.

The carrier 33, being free to arm, responds to the centrifugal force acting upon its weights, thereby bringing its detonator 33 into alignment with the ring pin 49 and the rest of the explosive train. In striking the target (a position suggested by Fig. 16), the ring pin d8 and yoke spring 'l5 are driven to the rear, striking the detonator 38 and rlng the explosive train.

As previously pointed out, the remaining fuzes are of insensitive types. They are intended to function instantaneously upon impact, but against more durable structures such as the framing and armored parts of an aircraft or the like. In each of Figs. 17 to ,2l the turnable type of carrier 33 is used, as are also the spring-pressed detent plugs 62. The latter move outwardly under the influence of centrifugal force when the projectile is red so that the carrier 33 is free to arm by aligning its detonator 33 with the firing pin 49 and the rest of the explosive train.

In Fig. 1'7 the firing pin pad l2 is xed in the base of a crushable housing Tl. This housing is slidable in the bore 5 l, which is closed at its outer end by a heavy disc 38. This disc is secured by the nose crimp 54. Upon striking the target the heavy nose disc 'I8 is driven inwardly, crushing the ring pin housing Tl and driving the firing pin into the previously aligned explosive train.

In Fig. 18 the partition 45, previously appearing as a thin disc, is now made in the form of a heavy body which, because of its volume, is capable of firing the detonator 33. The bore 5| is unoccupied except by the disc 53 which is held in place by the nose crimp 513, Upon striking the target, the previously armed detonator 38 is exploded by the violent shock imparted to it by means of the discs 53 and 45 and the collapsing front part of the nose cap 3 l.

Fig. 19 illustrates a variation of the fuze in Fig. 18 in -that the turnable carrier 33 is placed nearer to the front end with a view toward compactness. The forward side of the carrier 33 extends into the chamber Q9 into confronting relationship with a wall 'i9 which separates said chamber from the bore 5i except for a central orifice 89. Upon striking the target the fuze in Fig. 19 will function solely by the ensuing violent shock imparted to it by the impact.

In Fig. 20 the structural parts are the same as in Fig. 19 except that the sealing disc 53 is made of a `heavy body as in Fig. 17 and forms the base for the ring pin dc. The detonation of the explosive train upon impact of the fuze with the target is much the same as in Figs, 18 and 19 with the added positive functioning of the iiring pin as in Fig. 17.

Fig. 21 illustrates the simplest of all of the fuzes. The nose cap 3i is blind as at 3l. Upon striking the target the detonator 38 is initiated by the violent shock imparted to it upon the collapse of the nose cap.Y

While the various modifications disclosed herein are :to be regarded as preferred forms of the invention, it will be understood by those skilled in the art that further modifications and changes may be made without departing from the spirit oi the invention or the scope of the appended claims.

' The invention herein described may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

What is claimed as new and desired to be securedv by Letters Patent of the United States is:V

1. In a fuze, a body having a chamber and a lead included in a portion of an explosive train, a detonator carrier occupying said chamber initially assuming an unarmed position therein and being susceptible to centrifugal force set .up in the flight of the fuze to align its detonator with said lead to complete said train, a firing pin engaging the carrier to hold it in said unarmed position, a sleeve carrying the ring pin, said sleeve having a frangible portion, tension means acting on the sleeve tending to displace the firing pin into an armed position, and a collar loose on the sleeve initially abutted by said frangible portion to resist said tension means, said collar responding to a set-back force to rupture the frangible portion and thus release the iiring pin.

2. In a fuze, a body having a chamber and a lead included in a portion of an explosive train, a detonator carrier occupying said chamber initially assuming an unarmed position therein and being susceptible to centrifugal force set up in the flight of the fuze to align its detonator with said lead to complete said train, a ring pin engaging the carrier to hold it in said unarmed position, a sleeve having a head in which said pin is set, said sleeve having a frangible portion, a spring pocketed in the sleeve acting against the head tending to displace the firing pin into an ar-med position, a collar loose on the sleeve, initially abutted by said frangible portion to resist said spring, said collar responding to a set-back force to rupture the frangible portion and thus release the firing pin, and stop means on the sleeve obstructed by the collar in the resulting action ofthe spring limiting the displacement of the ring pin.

3. In a fuze, a body, a movable detonator carrier in the body, a nose cap attached to the .body and having a chamber, a ring pin having one end confronting the carrier, a sleeve mounted in the nose cap and to which the other end of the ring pin is secured, a frangible portion projecting from the sleeve into the chamber, a set-back collar loose 0n the sleeve and occupying the chamber, and a spring acting on the sleeve, urging the frangible portion into engagement with the c01- lar so as to push the collar against one end of the chamber. Y Y

4. In a fuze, a fuze body, a detonator carrier movably mounted on the fuze body, a firing pin en-gaging the carrier to hold it in an initially unarmed position, means movablly mounted on the iuze body and carrying the firing pin, said means having a frangible portion, a set-back member loose on said movably mounted means in a position between the frangible portion and a part of the fuze body, and tension means .acting on said movably mounted means, tending to displace the firing pin into an armed position and simultaneously causing said frangible portion to keep the set-back member pressed against said part of the fuze body. f

5.In a fuze, a fuze body, a firing pin means movably mounted within said body for carrying said r'ing pin, said movably mounted means having integral external frangible means, a set-.back

9 Wall portion of the body, and compression means housed by said movably mounted means for transmitting pressure through the frangible means to the set-back member to keep said member initialiy seated against said Wall portion.

RAYMOND L. GRAUMANN. NILLIAM J. DONAHUE, JR.

REFERENCES CITED The folowing references are of record in the file of this patent:

UNITED STATES PATENTS YNanna ,Date Summerbelle Aug. 26,1930

Number 1,774,043

Number Number 0 

